AlGaN-Cladding Free Green Semipolar GaN Based Laser Diode with a Lasing Wavelength of 506.4 nm

We demonstrate electrically driven InGaN based laser diodes (LDs), with a simple AlGaN-cladding-free epitaxial structure, grown on semipolar (2021) GaN substrates. The devices employed In 0.06 Ga 0.94 N waveguiding layers to provide transverse optical mode confinement. A maximum lasing wavelength of 506.4 nm was observed under pulsed operation, which is the longest reported for AlGaN-cladding-free III-nitride LDs. The threshold current density ( J th ) for index-guided LDs with uncoated etched facets was 23 kA/cm 2 , and 19 kA/cm 2 after application of high-reflectivity (HR) coatings. A characteristic temperature ( T 0 ) value of ∼130 K and wavelength red-shift of ∼0.05 nm/K were confirmed.